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I just got a tumble compost bin and had planned on using the dead grass from our first mowing. My husband reminded me that we had pretreated it with a pre-emergent and fertilizer about a month before it was cut. Can I still use it in my compost?

Technically, the pre-emergent should NOT be in the leaves of the grass blades. The plants don't absorb any of that chemical...only the nitrogen and other goodies. The pre-emergent remains in the soil for up to 4 months to keep any new seeds from sprouting only.

At least, that's the way it's "supposed" to work. It's a valid concern and question, and I would do my research before taking what I say for gospel. But, the way I explained it is the way I understand it. To be sure, you could leave the compost for 4 months, and anything still ON the leaves would become ineffective, too.

I put pre-emergent down a couple of weeks ago without concern. But, had any gotten in the garden, I would have had a problem. All my veggies are coming up. Just be careful when spreading close to the SFG.